The present invention relates generally to the cooling of heat generating surfaces and objects. More specifically, the present invention relates to apparatuses for dissipating heat generated by such objects. In addition, the present invention relates to cooling of heat generating objects by use of composite materials and devices without the use of external fans to assist in cooling.
In industry, there are various parts and components that generate heat during operation. For example, in the electronics and computer industries, it is well known that computer components generate heat during operation. Various types of electronic device packages and integrated circuit chips, such as the PENTIUM central processing unit chip (CPU) manufactured by Intel Corporation and RAM (random access memory) chips are such devices that generate heat. These integrated circuit devices, particularly the CPU microprocessor chips, generate a great deal of heat during operation which must be removed to prevent adverse effects on operation of the system into which the device is installed. For example, a PENTIUM microprocessor, containing millions of transistors, is highly susceptible to overheating which could destroy the microprocessor device itself or other components proximal to the microprocessor.
There are a number of prior art methods to cool heat generating components and objects to avoid device failure and overheating, as discussed above. A block heat sink or heat spreader is commonly placed into communication with the heat generating surface of the object to dissipate the heat therefrom. Such a heat sink typically includes a base member with a number of individual cooling members, such as fins, posts or pins, to assist in the dissipation of heat. The geometry of the cooling members is designed to improve the surface area of the heat sink with the ambient air for optimal heat dissipation. The use of such fins, posts of pins in an optimal geometrical configuration greatly enhances heat dissipation compared to devices with no such additional cooling members, such as a flat heat spreader.
To further enhance air flow and resultant heat dissipation, fans and devices have been used, either internally or externally. However, these external devices consume power and have numerous moving parts. As a result, heat sink assemblies with active devices are subject to failure and are much less reliable than a device which is solely passive in nature.
It has been discovered that more efficient cooling of electronics can be obtained through the use of passive devices which require no external power source and contain no moving parts. It is very common in the electronics industry to have many electronic devices on a single circuit board, such as a motherboard.
There have been many prior art attempts to provide effective and efficient cooling to an array of devices on a circuit board that need to be cooled. Use of bulk heat sinks are expensive and cumbersome. Individual heat sinks for each device to be cooled are typically the same configuration which presents problems in effectively cooling devices in the middle of the array because they are not exposed directly to air flow within the environment at hand. For example, the outer heat sink assemblies in a row of heat sink assemblies installed on a corresponding row of RAM chips obstruct or block the flow of air within an environment from contacting the inner heat sink assemblies within a row. As a result, the heat dissipation of the heat sink assemblies in the middle of the row will provide inferior heat dissipation to the outer heat sink assemblies that are directly exposed to air flow within an environment.
Therefore, there is a demand for a passive heat sink assembly with no moving parts that can provide heat dissipation without the use of active components. In addition, there is a demand for a complete heat sink assembly that can provide greatly enhanced heat dissipation over prior art passive devices with improved heat sink geometry. There is a particular demand for a heat sink assembly to be customizable to given air flow environment. Further, there is a demand for a heat sink assembly that can be customized to be unique from other similar heat sink assemblies within an array to permit direct air flow to each of the heat sink assemblies in the in the array for maximum heat dissipation in each of the devices to be cooled in the array.
The present invention preserves the advantages of prior art heat dissipation devices, heat exchangers and heat spreaders. In addition, it provides new advantages not found in currently available devices and overcomes many disadvantages of such currently available devices.
The invention is generally directed to the novel and unique U-shaped heat sink assembly. The assembly of the present invention is net-shape molded of a thermally conductive polymer composition. The present invention relates to a molded heat sink assembly for dissipating heat from a heat generating source, such as a computer semiconductor chip or electronic components on a computer circuit board, such as a video card.
A net-shape moldable U-shaped heat sink assembly formed by injection molding of a thermally conductive polymer composite material is shown. The heat sink assembly includes a base member with a number of integrated fin members thereon. A right upstanding wall extends from a first side of the base member and a left upstanding wall extends from a second side of the base member to form a substantially U-shaped heat sink assembly. To enhance thermal conductivity, fin members may be integrally formed into the base member, right wall and/or left wall during the molding of the heat sink assembly. Also, a flexible metallic substrate or hinges may be embedded within the U-shaped heat sink assembly to permit positioning of the right wall and left wall relative to the base member for custom configuration of the heat sink assembly.
Further, since the heat sink assembly is injection molded, there is tremendous flexibility in the arrangement of all the arms, fins and base of the molded heat sink assembly. These various components may be easily optimized to suit the application at hand. For example, the fins may have different patterns, such as a radial or pin grid array, to suit the heat dissipation environment at hand.
As will be discussed in detail below, it is preferred that one base member and two opposing walls be provided for ease of assembly and installation. However, more than two upstanding walls may be provided to better suit different heat dissipating environments.
It is therefore an object of the present invention to provide a heat dissipating device that can provide enhanced heat dissipation for a heat generating component or object.
It is an object of the present invention to provide a heat dissipating device that can provide heat dissipation for semiconductor devices on a circuit board, such as a motherboard or video card.
A object of the present invention is to provide a heat sink assembly that can be easily customized to accommodate different heat dissipating environments.
It is another object of the present invention to provide an array of heat sink assemblies that can accommodate an array of heat generating objects while maximizing heat transfer.
It is a further object of the present invention to provide a heat dissipating device that has no moving parts.
Another object of the present invention is to provide a heat dissipating device that is completely passive and does not consume power.
A further object of the present invention is to provide a heat dissipation device that is inexpensive to manufacture.
Another object of the present invention is to provide a heat dissipation device that has a thermal performance greater than conventional heat sink designs.
A object of the present invention is to provide a heat dissipation device that is net-shape moldable and has an optimal fin configuration.